Semiconductor and micro electro mechanical systems (MEMS) devices require myriad manufacturing processes to form the required complex electrical and mechanical structures. These devices are continually being reduced in size, resulting in associated tighter manufacturing process tolerances. One such manufacturing process employed is a plasma-assisted etch process.
Manufacturing variables of an etch process may result in a broad statistical distribution for the dimensions of the structures formed within a group of wafers being etched. Moreover, variability in the manufacturing process can also cause statistical distributions in structural dimensions within a single wafer. Such variations may be too great to enable efficient production of the devices.
For example, during the manufacture of semiconductor or MEMS devices, trenches are often etched into substrate materials. Although it is often desirable to etch trenches that have a uniform depth across the wafer and do not vary from wafer to wafer, it may be difficult to etch such structures.